EP0161648B1 - Electrophotographic recording material - Google Patents

Electrophotographic recording material Download PDF

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Publication number
EP0161648B1
EP0161648B1 EP85105785A EP85105785A EP0161648B1 EP 0161648 B1 EP0161648 B1 EP 0161648B1 EP 85105785 A EP85105785 A EP 85105785A EP 85105785 A EP85105785 A EP 85105785A EP 0161648 B1 EP0161648 B1 EP 0161648B1
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EP
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Prior art keywords
layer
recording material
organic
weight
type conducting
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EP85105785A
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German (de)
French (fr)
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EP0161648A1 (en
EP0161648B2 (en
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Jürgen Dr. Dipl.-Chem. Lingnau
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Hoechst AG
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Hoechst AG
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
    • G03G5/0601—Acyclic or carbocyclic compounds
    • G03G5/0609—Acyclic or carbocyclic compounds containing oxygen
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G03G5/06—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor characterised by the photoconductive material being organic
    • G03G5/0622—Heterocyclic compounds
    • G03G5/0644—Heterocyclic compounds containing two or more hetero rings
    • G03G5/0646—Heterocyclic compounds containing two or more hetero rings in the same ring system
    • G03G5/0657—Heterocyclic compounds containing two or more hetero rings in the same ring system containing seven relevant rings

Definitions

  • the invention relates to an electrophotographic recording material consisting of an electrically conductive layer support, optionally an insulating barrier layer and a photoconductive layer, the photoconductive layer containing at least one organic, n-conductive pigment, at least one electronically inert binder and photoconductor containing carbonyl groups.
  • the recording material is suitable for repeated or single use in copiers, as a printing form or as a printed circuit.
  • Color pigments that generate charge carriers include perinones (DE-OS 2 239 923, corresponding to GB-PS 1 416 603, DE-OS 2 108 958, corresponding to US-PS 3 879 200), perylenetetracarboxylic acid diimides (DE-OS 2 237 539, correspondingly US-PS 3 871 882, DE-OS 2 108 992, corresponding to US-PS 3 904 407) and condensed quinones (DE-OS 2 237 678, corresponding to US-PS 4 315 981, DE-OS 2 108 935, corresponding to US -PS 3 877 935) is used.
  • perinones DE-OS 2 239 923, corresponding to GB-PS 1 416 603, DE-OS 2 108 958, corresponding to US-PS 3 879 200
  • perylenetetracarboxylic acid diimides DE-OS 237 539, correspondingly US-PS 3 871 882, DE-OS 2 108 992,
  • a double-layer structure with a lower layer which generates charge carriers and has a low layer thickness with a high color pigment concentration and a relatively thick charge transport layer composed of inert binder and organic p-conducting photoconductor.
  • layer arrangements are specified in which the sensitizing color pigment and the p-type photoconductor are applied together in one layer on the electrically conductive layer support.
  • the concentration of the color pigment is only 0.1 to 5% by volume of the photoactive layer.
  • organic p-conducting photoconductor - aromatic or heterocyclic compounds - must be present in the layer in a concentration of at least 25 percent by volume in order to achieve sensibilities which can be used in practice.
  • Electronically inert polymers such as polystyrene, polyacrylate, cellulose nitrate, polyvinyl acetate, chlorinated rubber and the like are described as binders. v. a.
  • Electrophotographic layers consist of a photoconductive pigment and an electronically inert binder.
  • Zinc oxide for example in US Pat. No. 3,121,006, cadmium sulfide, for example in US Pat. No. 3,238,150, and a number of other inorganic compounds are described as photoconductive pigments.
  • the charge transport in these layers is achieved by a high concentration of the photoconductive pigment. With such a layer structure, a pigment concentration of over 50 percent by volume is required in order to enable particle contact of the photoconductive particles.
  • DE-OS 3 227 475 corresponding to US Pat. No.
  • part of the inorganic pigment can also be replaced by organic, photoconductive pigments, the pigments such as CI Pigment Red 168 and CI Pigment Orange 43 having proven themselves equally well Represent derivatives of naphthalene tetracarboxylic acid diimides.
  • the total amount of photoconductor in the layer required for practical use is between 20 and 80 percent by weight.
  • binders - because of their use for electrophotographic offset printing plates - alkaline stripping or dispersing polymers are claimed.
  • n-conductor Due to the fact that light absorption and charge carrier generation preferentially occur in the upper region of the layer and that the transport properties for electrons and electron holes are different (“n-conductor”), good sensitivity is only observed for zinc oxide layers with negative charging.
  • monolayers for positive charging can also be produced from Cu-phthalocyanine in s-form (JP-AS 0/38543).
  • the resulting ⁇ grain complex shows good sensitivity with poly-N-vinylcarbazole as a binder / p-type photoconductor (50:50).
  • photoconductors with a double layer arrangement are used.
  • this arrangement has the disadvantage that it is produced in two coating application steps, which is more complex than the production of a monolayer material. It is also disadvantageous in the case of double-layer arrangements that they have an unfavorable residual charge behavior.
  • monolayers based on zinc oxide can be used for cyclic image reproduction, which have low residual charge potentials. Because of the large amount of zinc oxide however, layers of this type show a relatively low mechanical stability and a relatively poor charge acceptance.
  • Double-layer photoconductors with a roughly equal pre-coat of pigment and binder and top coat of p-conductive photoconductor and binder according to German patent application, file number P 33 29 442.9, can be used for the electrophotographic production of offset printing plates, but are significantly less sensitive than the first and from Manufacturing costs also unfavorable.
  • Monolayer photoconductors with dissolved sensitizing dyes (DE-OS 2 526 720, corresponding to US Pat.
  • No. 4,063,948 show similar sensitivities, but are, in contrast to the pigment layers, sensitive to pre-exposure, i. H. their charge acceptance is significantly impaired by prior exposure. Monolayers with low concentrations of sensitizing pigment show poorer image reproduction in addition to significantly lower photosensitivity than the double layers. Common to all of the layer arrangements described, however, are undesired, relatively large residual potentials after the end of the exposure, which increase drastically with increasing layer thickness and lead to difficulties in making the latent charge image visible.
  • the present invention was therefore based on the object of providing an electrophotographic recording material which can be produced simply and inexpensively, has great photosensitivity and large voltage contrasts with good negative charge acceptance and leads to low residual potentials after exposure. At the same time, the mechanical properties should enable use on a flexible substrate or a lamination step.
  • Another object of the invention was to make the recording material applicable for the production of printing forms and printed circuits (printed circuit boards) by using suitable binders and low concentration of the p-type photoconductor.
  • the photoconductive layer is the organic n-conductive pigment selected from a compound of the class of the trans-perinones, the perylene-tetracarboxylic acid diimides or the condensed one Quinones, in a concentration between 10 and 50 percent by weight, based on the layer weight, and as photoconductor organic p-type photoconductor in a concentration of zero to 20 percent by weight, based on the layer weight.
  • the recording material in the photoconductive layer contains the organic n-type pigment in a concentration between 15 and 30 percent by weight and the organic p-type photoconductor in a concentration of 2 to 8 percent by weight, based on the layer weight.
  • concentrations of 20-30 percent by weight for the organic, n-type pigment and of 2-5 percent by weight for the organic, p-type photoconductor have proven successful.
  • the organic p-type photoconductor can be present in the layer in a homogeneously distributed form, but it can also be present in a gradient distribution by diffusion into the layer or else in a step-like distribution by double-layer arrangement.
  • pigments are referred to in a number of publications as photoconductive, which means, however, that photoconductivity is regularly understood in cooperation with other photoconductors.
  • the color pigments play the role of the sensitizer, which forms charge carriers in cooperation with the p-type photoconductor.
  • pigments are used either in very thin layers that generate charge carriers or, in the case of homogeneous distribution, in a relatively low concentration. As described above, according to US Pat. No. 3,879,200 and US Pat. No. 3,904,407, good electrophotographic properties can only be achieved in these cases.
  • the utilization of the n-conductivity of pigments used according to the invention requires a minimum pigment concentration which, at about 10 percent by weight, based on the layer weight, is to be set. Excessively high pigment concentrations lead to a deterioration in the charge acceptance, so that approximately 50% by weight of pigment is to be regarded as the upper limit. Pigment concentrations between 15 and 30 percent by weight have proven particularly successful. At these pigment concentrations, especially in the higher range, when the alkali-soluble binders according to the invention are used, the decoating ability of the photoconductive layer for use in electrophotographic imageable printing forms and the like remains. Like. Guaranteed.
  • n-type pigments When using n-type pigments according to the invention, an increase in sensitivity was found if p-type photoconductors were added to the layer to a small extent.
  • Compounds which are usually used in electrophotographic layers are suitable as such. Examples are oxdiazoles, oxazoles, aromatic amines, triphenylmethanes, hydrazones, but also polymeric compounds, such as polyvinyl carbazole, as are shown, for example, in German patents 10 58 836, 10 60 260, 1120875, 1197325 and 1068115 and 11 11 935.
  • the concentration of the p-type photoconductor should not exceed 20 percent by weight, based on the layer weight. Concentrations between 2 and 8 percent by weight have proven particularly useful.
  • the p-conductivity of the photoconductor only contributes to the generation of charge carriers and to the removal of the positive charge carriers in the upper region of the photoconductive layer.
  • the addition of p-type photoconductor can therefore also be restricted to these upper zones, which has proven to be advantageous particularly in the case of thicker layers in an arrangement in the upper region.
  • a targeted addition of the p-type photoconductor into the upper zones can be achieved either by a double-layer structure or by post-treatment of the finished layer not containing the p-type photoconductor with corresponding solutions of the photoconductor, which are applied without a binder.
  • Such electronically inert binders containing carbonyl groups are used which are soluble or dispersible in aqueous alkaline solution.
  • Copolymers of methacrylic acid esters and methacrylic acid, optionally with other monomers such as acrylic acid, styrene, are preferably used for this purpose.
  • binders whose glass transition temperature is significantly lower have proven suitable for use as an electrophotographic dry resist. Only in such a case can a complete transfer of the photoconductive layer be achieved with a lamination layer. Copolymers of the monomers acrylic acid, longer-chain acrylic or methacrylic acid esters, optionally in combination with other monomers such as methacrylic acid, styrene, have proven particularly useful as binders. There are no restrictions on the glass transition temperature of the binder for use as a liquid resist.
  • the thickness of the photoconductive layer depends primarily on the intended use. In order to ensure sufficient charge acceptance, it should not be less than about 3 g / m 2 . When used as a liquid resist or for the production of electrophotographic printing plates, it is expediently between about 5 and 30 g / m 2 , for photoconductor tapes or drums in copiers between about 10 and 20 g / m 2 and for laminatable material between about 20 and 50 g / m 2 , A sharp increase in the residual potential with the layer weight cannot be observed.
  • the coating with the photoconductive layer is carried out in the usual way from the solution, for example by doctor or spray application.
  • the application is preferably made with a flow machine.
  • the layer is dried, for example, in drying channels.
  • the recording material according to the invention can also be produced for the application of the dry resists by applying the photoconductive layer to the electrically conductive layer support by lamination under heat and pressure from an intermediate support, for example a polyethylene terephthalate film. Because of the relatively low proportion of p-type photoconductor, the recording material according to the invention can be in the form of a substrate and a coating Use solution as a liquid resist. In this case, it is up to the user to apply the coating using a wipe-on process.
  • Such a small layer thickness serves as an insulating barrier layer.
  • polymers can be used which bring about better adhesion of the photoconductive layer to the carrier material, for example UV or thermally curable systems.
  • these can also be insulating metal oxide layers, for example aluminum oxide, which bring about hydrophilization of the carrier surface.
  • the layer thickness of the insulating barrier layer should not exceed 4 g / m 2 .
  • Metals can be used as the electrically conductive layer supports, but plastic supports metallized by vapor deposition or lamination can also be used. In addition, plastics with a conductive coating made of polymeric binders and conductive materials such as metal powders or graphite dust can be used.
  • a conductive coating made of polymeric binders and conductive materials such as metal powders or graphite dust can be used.
  • plates made of roughened and anodized aluminum are preferably used as layer supports.
  • the preferred support is copper or has a copper surface such as copper clad polyamide film.
  • the layer contains substances which are added to the coating solution as conventional additives, which may be up to 5% by weight in the photoconductive layer. They improve the surface structure and the flexibility of the layer. These can be, for example, plasticizers, such as triphenyl phosphate, or leveling agents, such as silicone oils.
  • the layer obtained after drying is dark red and matt.
  • Hostapermorange GR Pigment Orange 43, CI 71 105, Formula 1
  • 10 g of polybutyl methacrylate R Plexigum P 676, Röhm GmbH
  • Example 2 The procedure was as in Example 2, with the difference that, instead of the oxdiazole mentioned, 1,5-diphenyl-3-p-methoxyphenylpyrazoline according to DE-AS 10 60 714, corresponding to US Pat. No. 3, 180, 729, and instead of the polybutyl methacrylate and the polymethyl methacrylate, a terpolymer of styrene, hexyl methacrylate and methacrylic acid in a molar ratio of 10:60:30 was used.
  • the coating was carried out on roughened and anodized aluminum support material in a layer thickness of about 6 g / m 2 .
  • the layer was treated with a dry developer after charging and imagewise exposure. After fixing it, it was possible to decoat with a commercially available decoater solution.
  • the resulting offset printing plate showed a high resolution and, in a printing test, gave good printing qualities up to a print run of well over 100,000.
  • Example 3 The procedure was as in Example 3, with the difference that instead of pyrazoline, 4-methoxybenzaldehyde diphenylhydrazone (DE-OS 32 46 036) and instead of Hostapermorange GR as dye N, N '- (3-methoxypropyl) perylene-tetracarboxylic acid- 3,4,9,10-diimide ( R Paliogen-black, BASF AG) was used.
  • Example 2 The procedure was as in Example 1, with the difference that the layer was applied to the layer support with a layer thickness of 20 g / m 2 .
  • Example 3 The procedure was as in Example 3, with the difference that copper-clad polyimide film was used instead of the anodized aluminum support.
  • the coated film obtained in this way could be stripped perfectly after the imaging and fixing of the toner image at the areas not covered by toner.
  • High-quality, flexible printed circuit boards were obtained by etching away the metal areas underneath.
  • a layer of 25% by weight of Hostapermorange GR and 75% by weight of the terpolymer from Example 3 with a layer weight of 3 g / m 2 was first applied to anodized aluminum supports.
  • a top coat of 25% by weight of Hostapermorange GR, 20% by weight of 2,5-bis- (4-diethylaminophenyl) -oxdiazole-1,3,4 and 55% by weight of the terpolymer was coated on this underlayer with a layer weight of 3 g / m 2 applied.
  • a primer (undercoat) of 6 g / m 2 was applied to an anodized aluminum support.
  • the dried layer was then treated with a solution of 5% by weight of 2,5-bis (4-diethylaminophenyl) oxdiazole-1,3,4 in tetrahydrofuran and dried again.
  • Analogous results can be achieved by treating the still wet primer with an oxdiazole solution (wet-on-wet coating).
  • Example 2 The procedure was as in Example 2, with the difference that a polyester ( R Dynapol L206, Dynamit Nobel AG) was used instead of the methacrylates.
  • the material thus obtained had a high degree of flexibility with good adhesion of the layer to the support. Even when used in cyclic copiers, it showed no change in the electrophotographic properties with the number of charging and exposure cycles.
  • Example 2 The procedure was as in Example 2, with the difference that a polyurethane ( R Desmolac 2100, Bayer AG) was used instead of the terpolymer.
  • a polyurethane R Desmolac 2100, Bayer AG
  • Example 2 The procedure was as in Example 2, with the difference that Hostapermscharlach GO (Formula IV, C.I. 59300) was used as pigment.
  • Hostapermscharlach GO Form IV, C.I. 59300
  • a charge transport layer from the following solution was applied to this charge carrier-generating layer, dry layer weight likewise 3 g / m 2 : 50 g of a copolymer of styrene and maleic anhydride and 50 g of 2,5-bis (4-diethylamino-phenyl) oxdiazole -1.3.4 were dissolved in 700 g of tetrahydrofuran and 250 g of butyl acetate with the addition of 0.1 g of silicone oil.
  • a monolayer with a layer weight of 6 g / m 2 from the following dispersion was applied to a roughened and anodized aluminum printing plate support: 6.25 g of Hostapermorange GR and 4.2 g of the terpolymer from Example 3 were in 50 g of tetrahydrofuran by milling in a ball mill for 2 hours dispersed or dissolved and then added to a solution of 50 g of 2,5-bis (4-diethylaminophenyl) -oxdiazole-1,3,4, 40 g of the terpolymer from Example 3 and 0.1 g of silicone oil in 850 g of tetrahydrofuran .
  • This example corresponds to a sensitive monolayer formulation described in U.S. Patent 3,879,200.
  • Example 3 The procedure was as in Example 3, with the difference that instead of the methacrylate terpolymer, a likewise aqueous-alkaline decoatable sulfonyl urethane (prepared according to DE-OS 32 10 577, Example 1) was used.
  • Example 2 The procedure was as in Example 2, with the difference that cellulose nitrate with a degree of nitration of 12.2% was used instead of the methacrylates.
  • Example 3 The procedure was as in Example 3, with the difference that instead of the trans-Perinon Hostapermorange GR, the analog cis compound Permanent red TG01 from Hoechst AG (C.I. 71110) was used.
  • E1 ⁇ 2, E1 ⁇ 4, and E1 ⁇ 8 mean the exposure energies that have to be applied at a light intensity of 3 / ⁇ W / cm 2 in order to achieve a discharge from -400 V to -200 V, -100 V and -50 V, respectively.

Abstract

An electrophotographic recording material is disclosed comprising an electrically conductive support, a photoconductive layer and, optionally, an insulating barrier layer between the substrate and photoconductive layer. The photoconductive layer comprises at least one organic, n-type conducting pigment in a concentration between 10 and 50, preferably between 15 and 30, percent by weight, relative to the photoconductive layer weight, at least one electronically inert, carbonyl group-containing binder and an organic, p-type conducting photoconductor in a concentration from 0 to 20, preferably from 2 to 8 percent by weight, relative to the photoconductive layer weight. The n-type conducting pigment preferably comprises a compound selected from the trans-perinones, the perylene-tetracarboxylic acid diimides, and the condensed quinones.

Description

Die Erfindung betrifft ein elektrophotographisches Aufzeichnungsmaterial, bestehend aus einem elektrisch leitenden Schichtträger, gegebenenfalls einer isolierenden Sperrschicht und einer photoleitfähigen Schicht, wobei die photoleitfähige Schicht mindestens ein organisches, n-leitendes Pigment, mindestens ein elektronisch inertes carbonylgruppenhaltiges Bindemittel und Photoleiter enthält. Das Aufzeichnungsmaterial ist geeignet zum wiederholten oder einmaligen Einsatz in Kopiergeräten, als Druckform oder als gedruckte Schaltung.The invention relates to an electrophotographic recording material consisting of an electrically conductive layer support, optionally an insulating barrier layer and a photoconductive layer, the photoconductive layer containing at least one organic, n-conductive pigment, at least one electronically inert binder and photoconductor containing carbonyl groups. The recording material is suitable for repeated or single use in copiers, as a printing form or as a printed circuit.

Es ist bekannt (DE-AS 1 117 391, entsprechend GB-PS 944 126), zur Herstellung von elektrophotographischen Aufzeichnungsmaterialien photoleitfähige, vorwiegend niedermolekulare, organische p-leitende Verbindungen zu verwenden und diese durch geeignete, gelöste Farbstoffe (DE-OS 2 526 720, entsprechend US-PS 4 063 948) oder auch dispergierte photoleitfähige Farbpigmente (DE-AS 2108 939, entsprechend US-PS 3 870 516) im sichtbaren Bereich des Spektrums zu sensibilisieren.It is known (DE-AS 1 117 391, corresponding to GB-PS 944 126) to use photoconductive, predominantly low molecular weight, organic p-conductive compounds for the production of electrophotographic recording materials and these by suitable, dissolved dyes (DE-OS 2 526 720 , corresponding to US Pat. No. 4,063,948) or dispersed photoconductive color pigments (DE-AS 2108 939, corresponding to US Pat. No. 3,870,516) in the visible region of the spectrum.

Als Ladungsträger erzeugende Farbpigmente werden unter anderem Perinone (DE-OS 2 239 923, entsprechend GB-PS 1 416 603, DE-OS 2 108 958, entsprechend US-PS 3 879 200), Perylentetracarbonsäurediimide (DE-OS 2 237 539, entsprechend US-PS 3 871 882, DE-OS 2 108 992, entsprechend US-PS 3 904 407) und kondensierte Chinone (DE-OS 2 237 678, entsprechend US-PS 4 315 981, DE-OS 2 108 935, entsprechend US-PS 3 877 935) verwendet. Den beschriebenen Systemen gemeinsam ist ein Doppelschichtaufbau mit einer Ladungsträger erzeugenden unteren Schicht geringer Schichtdicke mit hoher Farbpigmentkonzentration und einer relativ dicken Ladungstransportschicht aus inertem Bindemittel und organischem p-leitendem Photoleiter. Als weitere Ausführungsform werden Schichtanordnungen angegeben, in denen das sensibilisierende Farbpigment und der p-leitende Photoleiter gemeinsam in einer Schicht auf dem elektrisch leitenden Schichtträger aufgetragen sind. Um zu optimalen physikalischen und elektrischen Eigenschaften zu gelangen, beträgt zum Beispiel nach US-PS 3 879 200, die Konzentration des Farbpigments nur 0,1 bis 5 Volumprozent der photoaktiven Schicht. Der organische p-leitende Photoleiter - aromatische oder heterocyclische Verbindungen - muß hingegen in einer Konzentration von zumindest 25 Volumprozent in der Schicht enthalten sein, um praktisch verwendbare Empfindlichkeiten zu erzielen. Als Bindemittel werden elektronisch inerte Polymere beschrieben, wie Polystyrol, Polyacrylat, Cellulosenitrat, Polyvinylacetat, chlorierter Kautschuk u. v. a.Color pigments that generate charge carriers include perinones (DE-OS 2 239 923, corresponding to GB-PS 1 416 603, DE-OS 2 108 958, corresponding to US-PS 3 879 200), perylenetetracarboxylic acid diimides (DE-OS 2 237 539, correspondingly US-PS 3 871 882, DE-OS 2 108 992, corresponding to US-PS 3 904 407) and condensed quinones (DE-OS 2 237 678, corresponding to US-PS 4 315 981, DE-OS 2 108 935, corresponding to US -PS 3 877 935) is used. Common to the systems described is a double-layer structure with a lower layer which generates charge carriers and has a low layer thickness with a high color pigment concentration and a relatively thick charge transport layer composed of inert binder and organic p-conducting photoconductor. As a further embodiment, layer arrangements are specified in which the sensitizing color pigment and the p-type photoconductor are applied together in one layer on the electrically conductive layer support. In order to achieve optimal physical and electrical properties, for example according to US Pat. No. 3,879,200, the concentration of the color pigment is only 0.1 to 5% by volume of the photoactive layer. In contrast, the organic p-conducting photoconductor - aromatic or heterocyclic compounds - must be present in the layer in a concentration of at least 25 percent by volume in order to achieve sensibilities which can be used in practice. Electronically inert polymers such as polystyrene, polyacrylate, cellulose nitrate, polyvinyl acetate, chlorinated rubber and the like are described as binders. v. a.

Es sind ferner elektrophotographische Schichten bekannt, die aus einem photoleitfähigen Pigment und einem elektronisch inerten Bindemittel bestehen. Als photoleitfähige Pigmente werden Zinkoxid, zum Beispiel in US-PS 3 121 006, Cadmiumsulfid, zum Beispiel in US-PS 3 238 150, und eine Reihe anderer anorganischer Verbindungen beschrieben. Der Ladungstransport wird in diesen Schichten durch eine hohe Konzentration des photoleitfähigen Pigments erzielt. Bei einem solchen Schichtaufbau wird eine Pigmentkonzentration von über 50 Volumprozent gefordert, um einen Partikel-Kontakt der photoleitfähigen Partikeln zu ermöglichen. Nach DE-OS 3 227 475, entsprechend US-PS 4 418 134, läßt sich ein Teil des anorganischen Pigments auch durch organische, photoleitfähige Pigmente ersetzen, wobei sich die Pigmente wie C. I. Pigment Rot 168 und C. I. Pigment Orange 43 gleichermaßen bewährt haben, die Derivate der Naphthalintetracarbonsäurediimide darstellen. Der für eine praktische Anwendung erforderliche Gesamtphotoleiteranteil an der Schicht liegt dabei zwischen 20 und 80 Gewichtsprozent. Als Bindemittel werden - wegen der Anwendung für elektrophotographische Offset-Druckplatten - alkalisch entschichtbare bzw. dispergierbare Polymerisate beansprucht.Electrophotographic layers are also known which consist of a photoconductive pigment and an electronically inert binder. Zinc oxide, for example in US Pat. No. 3,121,006, cadmium sulfide, for example in US Pat. No. 3,238,150, and a number of other inorganic compounds are described as photoconductive pigments. The charge transport in these layers is achieved by a high concentration of the photoconductive pigment. With such a layer structure, a pigment concentration of over 50 percent by volume is required in order to enable particle contact of the photoconductive particles. According to DE-OS 3 227 475, corresponding to US Pat. No. 4,418,134, part of the inorganic pigment can also be replaced by organic, photoconductive pigments, the pigments such as CI Pigment Red 168 and CI Pigment Orange 43 having proven themselves equally well Represent derivatives of naphthalene tetracarboxylic acid diimides. The total amount of photoconductor in the layer required for practical use is between 20 and 80 percent by weight. As binders - because of their use for electrophotographic offset printing plates - alkaline stripping or dispersing polymers are claimed.

Aufgrund der Tatsache, daß es zur Lichtabsorption und Ladungsträgererzeugung bevorzugt im oberen Bereich der Schicht kommt, und daß die Transporteigenschaften für Elektronen und Elektronenlöcher unterschiedlich sind (« n-Leiter •), wird für Zinkoxid-Schichten eine gute Empfindlichkeit nur bei negativer Aufladung beobachtet.Due to the fact that light absorption and charge carrier generation preferentially occur in the upper region of the layer and that the transport properties for electrons and electron holes are different (“n-conductor”), good sensitivity is only observed for zinc oxide layers with negative charging.

Gute Empfindlichkeiten bei positiver Aufladung hingegen werden dann mit Monoschichtphotoleitersystemen erzielt, wenn sie neben einem inerten Bindemittel metallfreies Phthalocyanin in X-Form enthalten (DE-OS 1 497 205, entsprechend US-PS 3 816 118). Die dabei erforderliche Pigmentkonzentration zwischen 5 und 25 Gewichtsprozent liegt deutlich unter dem Wert, den man für einen Kontakt zwischen den Pigmentpartikeln annimmt.In contrast, good sensitivities with positive charging are achieved with monolayer photoconductor systems if, in addition to an inert binder, they contain metal-free phthalocyanine in X form (DE-OS 1 497 205, corresponding to US Pat. No. 3,816,118). The pigment concentration between 5 and 25 percent by weight required is well below the value assumed for contact between the pigment particles.

In analoger Weise lassen sich auch Monoschichten für positive Aufladung aus Cu-Phthalocyanin in s-Form (JP-AS 0/38543) herstellen.In an analogous manner, monolayers for positive charging can also be produced from Cu-phthalocyanine in s-form (JP-AS 0/38543).

Es ist auch bekannt, daß sich das Pigment C. I. Pigment Orange 43 (= C. 1. Vat Orange 7) gemäß JP-AS 49/76933 durch Umsetzung mit 2,4,7,8-Tetra-nitrocarbazol in eine photoleitfähige Form bringen läßt. Der entstehende π-Kornplex zeigt mit Poly-N-vinylcarbazol als Bindemittel/p-leitender Photoleiter (50 : 50) gute Empfindlichkeiten.It is also known that the pigment CI Pigment Orange 43 (= C. 1. Vat Orange 7) according to JP-AS 49/76933 can be converted into a photoconductive form by reaction with 2,4,7,8-tetra-nitrocarbazole . The resulting π grain complex shows good sensitivity with poly-N-vinylcarbazole as a binder / p-type photoconductor (50:50).

Um bei negativer Aufladung große Lichtempfindlichkeiten zu erzielen, werden Photoleiter mit Doppelschichtanordnung eingesetzt. Diese Anordnung hat jedoch den Nachteil, daß ihre Herstellung in zwei Beschichtungsantragsschritten erfolgt, was aufwendiger als die Herstellung eines Monoschichtmaterials ist. Bei Doppelschichtanordnungen ist auch nachteilig, daß sie ein ungünstiges Restladungsverhalten aufweisen. Demgegenüber lassen sich Monoschichten auf Zinkoxid-Basis für die cyclische Bildwiedergabe einsetzen, die niedrige Restladungspotentiale besitzen. Aufgrund des großen Zinkoxid-Anteils zeigen Schichten dieser Art jedoch eine relativ geringe mechanische Stabilität und eine relativ schlechte Ladungsannahme.In order to achieve high light sensitivity with negative charging, photoconductors with a double layer arrangement are used. However, this arrangement has the disadvantage that it is produced in two coating application steps, which is more complex than the production of a monolayer material. It is also disadvantageous in the case of double-layer arrangements that they have an unfavorable residual charge behavior. In contrast, monolayers based on zinc oxide can be used for cyclic image reproduction, which have low residual charge potentials. Because of the large amount of zinc oxide however, layers of this type show a relatively low mechanical stability and a relatively poor charge acceptance.

Für die Anwendung zur Herstellung von elektrophotographischen Druckformen oder gedruckten Schaltungen ist die Entschichtbarkeit der Photoleiterschicht an den Nichtbildstellen nach Bebilderung und Fixierung des Tonerbildes ein entscheidendes Kriterium. Daher sind Photoleiterschichten in Doppelschichtanordnung mit extrem hohen Pigmentanteilen nicht gut einsetzbar. Doppelschichtphotoleiter mit etwa gleich starkem Vorstrich aus Pigment und Bindemittel und Deckstrich aus p-leitendem Photoleiter und Bindemittel gemäß deutscher Patentanmeldung, Aktenzeichen P 33 29 442.9, lassen sich für die elektrophotographische Herstellung von Offset-Druckplatten verwenden, sind aber deutlich unempfindlicher als die erstgenannten und vom Herstellungsaufwand ebenfalls ungünstig. Monoschichtphotoleiter mit gelösten Sensibilisierungsfarbstoffen (DE-OS 2 526 720, entsprechend US-PS 4 063 948) zeigen ähnliche Empfindlichkeiten, sind aber im Gegensatz zu den Pigmentschichten vorbelichtungsempfindlich, d. h. ihre Ladungsannahme wird durch vorherige Belichtung deutlich verschlechtert. Monoschichten mit niedrigen Konzentrationen an sensibilisierendem Pigment zeigen neben einer, verglichen mit den Doppelschichten, deutlich niedrigeren Lichtempfindlichkeit, schlechtere Bildwiedergaben. Allen beschriebenen Schichtanordnungen gemeinsam sind jedoch unerwünschte, relativ große Restpotentiale nach dem Ende der Belichtung, die mit zunehmender Schichtdicke drastisch ansteigen und zu Schwierigkeiten beim Sichtbarmachen des latenten Ladungsbildes führen.For the application for the production of electrophotographic printing forms or printed circuits, the decoating ability of the photoconductor layer at the non-image areas after imaging and fixing of the toner image is a decisive criterion. For this reason, photoconductor layers in a double-layer arrangement with extremely high pigment contents cannot be used well. Double-layer photoconductors with a roughly equal pre-coat of pigment and binder and top coat of p-conductive photoconductor and binder according to German patent application, file number P 33 29 442.9, can be used for the electrophotographic production of offset printing plates, but are significantly less sensitive than the first and from Manufacturing costs also unfavorable. Monolayer photoconductors with dissolved sensitizing dyes (DE-OS 2 526 720, corresponding to US Pat. No. 4,063,948) show similar sensitivities, but are, in contrast to the pigment layers, sensitive to pre-exposure, i. H. their charge acceptance is significantly impaired by prior exposure. Monolayers with low concentrations of sensitizing pigment show poorer image reproduction in addition to significantly lower photosensitivity than the double layers. Common to all of the layer arrangements described, however, are undesired, relatively large residual potentials after the end of the exposure, which increase drastically with increasing layer thickness and lead to difficulties in making the latent charge image visible.

Für die Anwendung als elektrophotographischer Resist lassen sich Monoschichten aus Bindemittel, gelöstem Farbstoff oder Pigment und p-leitendem Photoleiter nur über Laminierungsverfahren einsetzen. Ein direktes Auftragen auf Metalle, wie Kupfer oder Eisen, führt oft wegen des hohen Photoleiteranteils zu einer Vergiftung der Schicht oder Oberfläche und dadurch zu einer stark verminderten Ladungsannahme, die eine praktische Anwendung stark behindert. Mit Doppelschichten, die p-leitenden-Photoleiter im Vorstrich nicht enthalten, lassen sich diese Effekte zwar umgehen, wobei jedoch wiederum die oben genannten Nachteile auftreten.For use as an electrophotographic resist, monolayers composed of binder, dissolved dye or pigment and p-type photoconductor can only be used via lamination processes. Direct application to metals such as copper or iron often leads to poisoning of the layer or surface due to the high proportion of photoconductors and thus to a greatly reduced charge acceptance, which greatly hinders practical use. These effects can be avoided with double layers which do not contain p-conducting photoconductors in the primer, but again the disadvantages mentioned above occur.

Der vorliegenden Erfindung lag daher die Aufgabe zugrunde, ein elektrophotographisches Aufzeichnungsmaterial zu schaffen, das einfach und billig herstellbar ist, eine große Lichtempfindlichkeit und große Spannungskontraste bei guter negativer Ladungsannahme aufweist und nach der Belichtung zu niedrigen Restpotentialen führt. Gleichzeitig sollen die mechanischen Eigenschaften eine Verwendung auf flexiblem Schichtträger bzw. einen Laminierungsschritt ermöglichen. Weiteres Ziel der Erfindung war es, durch Verwendung geeigneter Bindemittel und geringer Konzentration des p-ieitenden Photoleiters das Aufzeichnungsmaterial auch für die Herstellung von Druckformen und gedruckten Schaltungen (Leiterplatten) anwendbar zu machen.The present invention was therefore based on the object of providing an electrophotographic recording material which can be produced simply and inexpensively, has great photosensitivity and large voltage contrasts with good negative charge acceptance and leads to low residual potentials after exposure. At the same time, the mechanical properties should enable use on a flexible substrate or a lamination step. Another object of the invention was to make the recording material applicable for the production of printing forms and printed circuits (printed circuit boards) by using suitable binders and low concentration of the p-type photoconductor.

Die Lösung dieser Aufgabe geht aus von einem elektrophotographischen Aufzeichnungsmaterial der eingangs genannten Art, und sie ist dadurch gekennzeichnet, daß die photoleitfähige Schicht das organische n-leitende Pigment, ausgewählt aus einer Verbindung der Klasse der trans-Perinone, der Perylen-tetracarbonsäurediimide oder der kondensierten Chinone, in einer Konzentration zwischen 10 und 50 Gewichtsprozent, bezogen auf das Schichtgewicht, und als Photoleiter organischen p-leitenden Photoleiter in einer Konzentration von null bis 20 Gewichtsprozent, bezogen auf das Schichtgewicht, enthält. In bevorzugter Ausführungsform enthält das Aufzeichnungsmaterial in der photoleitfähigen Schicht das organische n-leitende Pigment in einer Konzentration zwischen 15 und 30 Gewichtsprozent und den organischen p-leitenden Photoleiter in einer Konzentration von 2 bis 8 Gewichtsprozent, bezogen auf das Schichtgewicht. Insbesondere haben sich Konzentrationen von 20-30 Gewichtsprozent für das organische, n-leitende Pigment und von 2-5 Gewichtsprozent für den organischen, p-leitenden Photoleiter bewährt.The solution to this problem is based on an electrophotographic recording material of the type mentioned at the outset, and it is characterized in that the photoconductive layer is the organic n-conductive pigment selected from a compound of the class of the trans-perinones, the perylene-tetracarboxylic acid diimides or the condensed one Quinones, in a concentration between 10 and 50 percent by weight, based on the layer weight, and as photoconductor organic p-type photoconductor in a concentration of zero to 20 percent by weight, based on the layer weight. In a preferred embodiment, the recording material in the photoconductive layer contains the organic n-type pigment in a concentration between 15 and 30 percent by weight and the organic p-type photoconductor in a concentration of 2 to 8 percent by weight, based on the layer weight. In particular, concentrations of 20-30 percent by weight for the organic, n-type pigment and of 2-5 percent by weight for the organic, p-type photoconductor have proven successful.

Dabei kann der organische p-leitende Photoleiter in homogen verteilter Form in der Schicht vorhanden sein, er kann aber auch durch Eindiffusion in die Schicht in gradientenförmiger Verteilung oder auch durch Doppelschichtanordnung in stufenförmiger Verteilung vorliegen.The organic p-type photoconductor can be present in the layer in a homogeneously distributed form, but it can also be present in a gradient distribution by diffusion into the layer or else in a step-like distribution by double-layer arrangement.

Als n-Ieitendes Pigment können Pigmente der folgenden allgemeinen Formeln I bis IV eingesetzt werden.

  • Trans-Perinone :
    Figure imgb0001
  • Perylentetracarbonsäurediimide :
    Figure imgb0002
  • Kondensierte Chinone :
    Figure imgb0003
    Figure imgb0004
    in denen
    • R für Wasserstoff, einen Phenylrest oder einen Alkylrest aus ein bis vier Kohlenstoffatomen steht, die durch Halogen, Alkyl- oder Alkoxygruppen substituiert sein können,
    • R' für Halogen, wie Chlor oder Brom, für die Nitro-, die Cyano- oder eine Alkoxygruppe steht,
    • n eine Zahl zwischen eins und vier ist.
Pigments of the following general formulas I to IV can be used as the n-conducting pigment.
  • Trans-Perinone:
    Figure imgb0001
  • Perylene tetracarboxylic acid diimides:
    Figure imgb0002
  • Condensed quinones:
    Figure imgb0003
    Figure imgb0004
     in which
    • R represents hydrogen, a phenyl radical or an alkyl radical of one to four carbon atoms, which can be substituted by halogen, alkyl or alkoxy groups,
    • R 'represents halogen, such as chlorine or bromine, represents the nitro, cyano or an alkoxy group,
    • n is a number between one and four.

Diese Pigmente werden in einer Reihe von Publikationen als photoleitfähig bezeichnet, womit jedoch regelmäßig Photoleitfähigkeit im Zusammenwirken mit anderen Photoleitern verstanden wird. Den Farbpigmenten kommt dabei die Rolle des Sensibilisators zu, der im Zusammenwirken mit dem p-leitenden Photoleiter Ladungsträger bildet. Dieser Rolle entsprechend werden Pigmente entweder in sehr dünnen Ladungsträger erzeugenden Schichten oder aber bei homogener Verteilung in relativ niedriger Konzentration eingesetzt. Wie oben beschrieben, lassen sich nach US-PS 3 879 200 und US-PS 3 904 407 nur in diesen Fällen gute elektrophotographische Eigenschaften erzielen.These pigments are referred to in a number of publications as photoconductive, which means, however, that photoconductivity is regularly understood in cooperation with other photoconductors. The color pigments play the role of the sensitizer, which forms charge carriers in cooperation with the p-type photoconductor. In accordance with this role, pigments are used either in very thin layers that generate charge carriers or, in the case of homogeneous distribution, in a relatively low concentration. As described above, according to US Pat. No. 3,879,200 and US Pat. No. 3,904,407, good electrophotographic properties can only be achieved in these cases.

Im Gegensatz hierzu wurde nun gefunden, daß Aufzeichnungsmaterialien, die Pigmente der allgemeinen Formeln I bis IV in hinreichend hohen Konzentrationen enthalten, die etwa den bei den Phthalocyaninen beschriebenen entsprechen, Photoleitfähigkeit auch dann zeigen, wenn kein p-leitender Photoleiter der Schicht zugesetzt wurde. Das stark unterschiedliche Verhalten bei positiver und negativer Aufladung weist auf eine ausgeprägte n-Leitfähigkeit dieser Pigmente hin. Gute Empfindlichkeiten lassen sich wie bei ZnO nur bei negativer Aufladung erzielen.In contrast to this, it has now been found that recording materials which contain pigments of the general formulas I to IV in sufficiently high concentrations, which correspond approximately to those described for the phthalocyanines, show photoconductivity even when no p-conducting photoconductor has been added to the layer. The strongly different behavior with positive and negative charging indicates a pronounced n-conductivity of these pigments. As with ZnO, good sensitivities can only be achieved with negative charging.

Überraschend und aufgrund des bislang Bekannten bei den erfindungsgemäß einsetzbaren Pigmenten nicht zu erwarten, war eine ausgeprägte Abhängigkeit der elektrophotographischen Eigenschaften der Schicht vom verwendeten Bindemittel. So konnten gute Empfindlichkeiten nur in Verbindung mit Bindemitteln erzielt werden, deren gemeinsames Merkmal eine Carbonylgruppe, z. B. in Form der Carboxygruppe, ist. Nitrocellulose dagegen, sonst ein Bindemittel mit besonders günstigen elektrophotographischen Eigenschaften, erwies sich in der erfindungsgemäßen photoleitfähigen Schicht als sehr ungünstig, ebenso zum Beispiel Polystyrol. Der Bindemittel-Einfluß bleibt auch dann unvermindert bestehen, wenn p-leitende Photoleiter der Schicht erfindungsgemäß in den aufgezeigten Mengen zugesetzt werden.Surprising and, due to what has been known to date, not to be expected for the pigments which can be used according to the invention, was a pronounced dependence of the electrophotographic properties of the layer on the binder used. So good sensitivities could only be achieved in connection with binders, the common feature of which is a carbonyl group, e.g. B. in the form of the carboxy group. In contrast, nitrocellulose, otherwise a binder with particularly favorable electrophotographic properties, proved to be very unfavorable in the photoconductive layer according to the invention, as was polystyrene, for example. The influence of the binder remains undiminished even if p-type photoconductors are added to the layer in the amounts indicated according to the invention.

Wie bei Zinkoxid-Schichten wird bei einem Teil der photoleitfähigen Schichten nach der Erfindung ein starker Trap-Effekt in der Anfangsphase der Entladung beobachtet, der zu einem S-förmigen Entladungsverlauf anstelle der sonst bei organischen Photoleitersystemen (z. B. DE-PS 2 237 539) näherungsweise exponentiellen Entladungscharakteristik führt. Diese S-förmige Entladungscharakteristik liefert besonders hohe Spannungskontraste im Bereich mittlerer Belichtungsenergien und läßt sich daher zur Herstellung von Ladungs- und Tonerbildern besonders harter Gradation und besonders hoher Auflösung verwenden.As with zinc oxide layers, a strong trap effect is observed in part of the photoconductive layers according to the invention in the initial phase of the discharge, which leads to an S-shaped discharge profile instead of that which otherwise occurs with organic photoconductor systems (e.g. DE-PS 2 237 539) leads to approximately exponential discharge characteristics. This S-shaped discharge characteristic provides particularly high voltage contrasts in the range of medium exposure energies and can therefore be used to produce charge and toner images of particularly hard gradation and particularly high resolution.

Die Ausnutzung der n-Leitfähigkeit von erfindungsgemäß verwendeten Pigmenten setzt eine Mindestpigmentkonzentration voraus, die, bei ca. 10 Gewichtsprozent, bezogen auf das Schichtgewicht, anzusetzen ist. Zu hohe Pigmentkonzentrationen führen zu einer Verschlechterung der Ladungsannahme, so daß etwa 50 Gewichtsprozent Pigment als Obergrenze anzusehen ist. Besonders bewährt haben sich Pigmentkonzentrationen zwischen 15 und 30 Gewichtsprozent. Bei diesen Pigmentkonzentrationen, besonders im höheren Bereich, bleibt bei Verwendung der erfindungsgemäßen, alkalilöslichen Bindemittel auch die Entschichtbarkeit der photoleitfähigen Schicht für die Anwendung in elektrophotographischen bebilderbaren Druckformen u. dgl. gewährleistet.The utilization of the n-conductivity of pigments used according to the invention requires a minimum pigment concentration which, at about 10 percent by weight, based on the layer weight, is to be set. Excessively high pigment concentrations lead to a deterioration in the charge acceptance, so that approximately 50% by weight of pigment is to be regarded as the upper limit. Pigment concentrations between 15 and 30 percent by weight have proven particularly successful. At these pigment concentrations, especially in the higher range, when the alkali-soluble binders according to the invention are used, the decoating ability of the photoconductive layer for use in electrophotographic imageable printing forms and the like remains. Like. Guaranteed.

Bei der erfindungsgemäßen Verwendung von n-leitenden Pigmenten wurde eine Erhöhung der Empfindlichkeiten gefunden, wenn man in geringem Umfang p-leitende Photoleiter der Schicht zusetzt. Als solche kommen dabei Verbindungen in Frage, die üblicherweise in elektrophotographischen Schichten Verwendung finden. Beispiele sind Oxdiazole, Oxazole, aromatische Amine, Triphenylmethane, Hydrazone, aber auch polymere Verbindungen, wie Polyvinylcarbazol, wie sie zum Beispiel aus den deutschen Patentschriften 10 58 836, 10 60 260, 1120875, 1197325 sowie 1068115 und 11 11 935 hervorgehen.When using n-type pigments according to the invention, an increase in sensitivity was found if p-type photoconductors were added to the layer to a small extent. Compounds which are usually used in electrophotographic layers are suitable as such. Examples are oxdiazoles, oxazoles, aromatic amines, triphenylmethanes, hydrazones, but also polymeric compounds, such as polyvinyl carbazole, as are shown, for example, in German patents 10 58 836, 10 60 260, 1120875, 1197325 and 1068115 and 11 11 935.

Um eine gute Ladungsannahme der photoleitfähigen Schicht zu gewährleisten, sollte die Konzentration des p-leitenden Photoleiters 20 Gewichtsprozent, bezogen auf das Schichtgewicht, nicht überschreiten. Bewährt haben sich insbesondere Konzentrationen zwischen 2 und 8 Gewichtsprozent.In order to ensure good charge acceptance of the photoconductive layer, the concentration of the p-type photoconductor should not exceed 20 percent by weight, based on the layer weight. Concentrations between 2 and 8 percent by weight have proven particularly useful.

Die p-Leitfähigkeit des Photoleiters trägt nur in dem oberen Bereich der photoleitfähigen Schicht zur Ladungsträgererzeugung und zum Abtransport der positiven Ladungsträger bei. Der Zusatz von p-leitendem Photoleiter kann sich daher erfindungsgemäß auch auf diese oberen Zonen beschränken, was sich insbesondere bei dickeren Schichten in einer Anordnung im oberen Bereich als vorteilhaft erweist. Eine gezielte Zugabe des p-leitenden Photoleiters in die oberen Zonen läßt sich entweder durch einen Doppelschichtaufbau erreichen oder durch eine Nachbehandlung der fertigen, den p-leitenden Photoleiter nicht enthaltenden Schicht mit entsprechenden Lösungen des Photoleiters, die ohne Bindemittel aufgetragen werden. Durch ein Anlösen des Bindemittels und anschließendes Eindiffundieren des p-leitenden Photoleiters werden so Lichtempfindlichkeiten erhalten, die denen homogen-dotierter Schichten entsprechen. Als Antragslösungen haben sich 5%ige Lösungen in zum Beispiel Tetrahydrofuran bewährt.The p-conductivity of the photoconductor only contributes to the generation of charge carriers and to the removal of the positive charge carriers in the upper region of the photoconductive layer. According to the invention, the addition of p-type photoconductor can therefore also be restricted to these upper zones, which has proven to be advantageous particularly in the case of thicker layers in an arrangement in the upper region. A targeted addition of the p-type photoconductor into the upper zones can be achieved either by a double-layer structure or by post-treatment of the finished layer not containing the p-type photoconductor with corresponding solutions of the photoconductor, which are applied without a binder. By dissolving the binder and then diffusing in the p-type photoconductor, light sensitivities are obtained which correspond to those of homogeneously doped layers. 5% solutions in, for example, tetrahydrofuran have proven themselves as application solutions.

Als elektronisch inerte carbonylgruppenhaltige Bindemittel haben sich sowohl Polymere mit C=0- haltigen Seitengruppen bewährt, als auch Polykondensate und Polyadditionsverbindungen mit C=0-Gruppen in der Hauptkette. Gute Lichtempfindlichkeiten wurden erreicht mit Homo- und Copolymerisaten der Vinylester, der Acryl- und Methacrylsäureester, der Acryl- und Methacrylsäure, der Vinylketone, der Acryl- und Methacrylsäureamide, sowie mit Polyestern, Polycarbonaten, Polyurethanen, Polyamiden und Polyharnstoffen. Aufgrund ihrer mechanischen Eigenschaft für flexible Photoleiter besonders geeignet sind Polyester und Polycarbonate.Polymers with C = 0-containing side groups, as well as polycondensates and polyaddition compounds with C = 0 groups in the main chain, have proven themselves as electronically inert binders containing carbonyl groups. Good light sensitivity was achieved with homopolymers and copolymers of vinyl esters, acrylic and methacrylic acid esters, acrylic and methacrylic acid, vinyl ketones, acrylic and methacrylic acid amides, and with polyesters, polycarbonates, polyurethanes, polyamides and polyureas. Due to their mechanical properties, polyesters and polycarbonates are particularly suitable for flexible photoconductors.

Zur Herstellung von Druckformen werden solche elektronisch inerte, carbonylgruppenhaltige Bindemittel eingesetzt, die in wäßrigalkalischer Lösung löslich oder dispergierbar sind. Hierfür sind Copolymerisate aus Methacrylsäureestern und Methacrylsäure, gegebenenfalls mit weiteren Monomeren, wie Acrylsäure, Styrol, bevorzugt einzusetzen.For the production of printing forms, such electronically inert binders containing carbonyl groups are used which are soluble or dispersible in aqueous alkaline solution. Copolymers of methacrylic acid esters and methacrylic acid, optionally with other monomers such as acrylic acid, styrene, are preferably used for this purpose.

Diese erweisen sich gegenüber den alkalilöslichen Bindemitteln auf Basis von Acrylsäure und Acrylsäureestern bzw. Vinylacetat und Crotonsäure überlegen. Dies gilt insbesondere für die Ladungsannahme, die bei den bevorzugt genannten Copolymerisaten höher ist bei unveränderter Lichtempfindlichkeit. Dies gilt aber auch für die Kriterien der Fixierbarkeit des auf der photoleitfähigen Schicht erhaltenen Tonerbildes, für die Entschichtbarkeit und für die spätere Druckauflage. Als günstig erweist sich hierfür eine Glasübergangstemperatur von > 40 °C.These are superior to the alkali-soluble binders based on acrylic acid and acrylic acid esters or vinyl acetate and crotonic acid. This applies in particular to the charge acceptance, which is higher in the case of the copolymers mentioned, with unchanged photosensitivity. However, this also applies to the criteria for fixability of the toner image obtained on the photoconductive layer, for decoating and for the subsequent print run. A glass transition temperature of> 40 ° C has proven to be favorable for this.

Für die Anwendung als elektrophotographischer Trockenresist erweisen sich nur solche Bindemittel als geeignet, deren Glasübergangstemperatur wesentlich niedriger liegt. Nur in einem solchen Fall läßt sich bei einer Laminierschicht ein vollständiges Übertragen der photoleitfähigen Schicht erzielen. Als Bindemittel haben sich Mischpolymerisate aus den Monomeren Acrylsäure, längerkettigen Acryl- oder Methacrylsäureestern, gegebenenfalls in Verbindung mit weiteren Monomeren, wie Methacrylsäure, Styrol besonders bewährt. Für die Anwendung als Flüssigresist bestehen die Einschränkungen bezüglich der Glasübergangstemperatur des Bindemittels nicht.Only those binders whose glass transition temperature is significantly lower have proven suitable for use as an electrophotographic dry resist. Only in such a case can a complete transfer of the photoconductive layer be achieved with a lamination layer. Copolymers of the monomers acrylic acid, longer-chain acrylic or methacrylic acid esters, optionally in combination with other monomers such as methacrylic acid, styrene, have proven particularly useful as binders. There are no restrictions on the glass transition temperature of the binder for use as a liquid resist.

Die Dicke der photoleitfähigen Schicht richtet sich in erster Linie nach dem beabsichtigten Verwendungszweck. Um eine ausreichende Ladungsannahme zu gewährleisten, soll sie etwa 3 g/m2 nicht unterschreiten. Bei Verwendung als Flüssigresist oder zur Herstellung von elektrophotographischen Druckplatten liegt sie zweckmäßig zwischen etwa 5 und 30 g/m2, für Photoleiterbänder oder -trommeln in Kopiergeräten zwischen etwa 10 und 20 g/m2 und für kaschierfähiges Material zwischen etwa 20 und 50 g/m2, Ein starker Anstieg des Restpotentials mit dem Schichtgewicht ist nicht zu beobachten.The thickness of the photoconductive layer depends primarily on the intended use. In order to ensure sufficient charge acceptance, it should not be less than about 3 g / m 2 . When used as a liquid resist or for the production of electrophotographic printing plates, it is expediently between about 5 and 30 g / m 2 , for photoconductor tapes or drums in copiers between about 10 and 20 g / m 2 and for laminatable material between about 20 and 50 g / m 2 , A sharp increase in the residual potential with the layer weight cannot be observed.

Die Beschichtung mit der photoleitenden Schicht erfolgt in üblicher Weise aus der Lösung, zum Beispiel durch Rakel- oder Sprühantrag. Vorzugsweise wird der Antrag mit einem Fließer vorgenommen. Die Trocknung der Schicht erfolgt beispielsweise in Trockenkanälen.The coating with the photoconductive layer is carried out in the usual way from the solution, for example by doctor or spray application. The application is preferably made with a flow machine. The layer is dried, for example, in drying channels.

Das erfindungsgemäße Aufzeichnungsmaterial kann für die Anwendung der Trockenresists auch dadurch hergestellt werden, daß man die photoleitfähige Schicht durch Laminieren unter Wärme und Druck von einem Zwischenträger, zum Beispiel einer Polyethylenterephthalatfolie, auf den elektrisch leitenden Schichtträger aufbringt. Aufgrund des relativ niedrigen Anteils an p-leitendem Photoleiter läßt sich das erfindungsgemäße Aufzeichnungsmaterial in Form von Schichtträger und einer Beschichtungslösung als Flüssigresist einsetzen. In diesem Fall bleibt es dem Anwender überlassen, die Beschichtung im Sinne eines wipe-on-Verfahrens vorzunehmen.The recording material according to the invention can also be produced for the application of the dry resists by applying the photoconductive layer to the electrically conductive layer support by lamination under heat and pressure from an intermediate support, for example a polyethylene terephthalate film. Because of the relatively low proportion of p-type photoconductor, the recording material according to the invention can be in the form of a substrate and a coating Use solution as a liquid resist. In this case, it is up to the user to apply the coating using a wipe-on process.

Als isolierende Sperrschicht dienen solche geringer Schichtdicke. Als solche können Polymere eingesetzt werden, die eine bessere Haftung der photoleitfähigen Schicht auf dem Trägermaterial bewirken, zum Beispiel UV- oder thermisch härtbare Systeme. Es kann sich dabei aber auch um isolierende Metalloxidschichten, zum Beispiel Aluminiumoxid, handeln, die eine Hydrophilierung der Trägeroberfläche bewirken. Um gute elektrophotographische Eigenschaften zu gewährleisten, sollte die Schichtdicke der isolierenden Sperrschicht 4 g/m2 nicht überschreiten.Such a small layer thickness serves as an insulating barrier layer. As such, polymers can be used which bring about better adhesion of the photoconductive layer to the carrier material, for example UV or thermally curable systems. However, these can also be insulating metal oxide layers, for example aluminum oxide, which bring about hydrophilization of the carrier surface. In order to ensure good electrophotographic properties, the layer thickness of the insulating barrier layer should not exceed 4 g / m 2 .

Als elektrisch leitende Schichtträger lassen sich Metalle, aber auch durch Bedampfung oder Kaschierung metallisierte Kunststoffträger anwenden. Darüberhinaus können Kunststoffe mit einer leitfähigen Beschichtung aus polymeren Bindemitteln und leitfähigen Materialien, wie Metallpulvern oder Graphitstaub, eingesetzt werden. Zur Herstellung von elektrophotographischen Druckformen werden als Schichtträger Platten aus aufgerauhtem und anodisiertem Aluminium bevorzugt verwendet. Für die Verwendung als elektrophotographischer Resist ist der bevorzugte Schichtträger aus Kupfer oder besitzt eine Kupferoberfläche, wie kupferkaschierte Polyamidfolie.Metals can be used as the electrically conductive layer supports, but plastic supports metallized by vapor deposition or lamination can also be used. In addition, plastics with a conductive coating made of polymeric binders and conductive materials such as metal powders or graphite dust can be used. For the production of electrophotographic printing plates, plates made of roughened and anodized aluminum are preferably used as layer supports. For use as an electrophotographic resist, the preferred support is copper or has a copper surface such as copper clad polyamide film.

Als übliche Zusätze, die in der photoleitfähigen Schicht bis zu 5 Gewichtsprozent enthalten sein können, enthält die Schicht Substanzen, die man der Beschichtungslösung zusetzt. Sie verbessern die Oberflächenstruktur und die Flexibilität der Schicht. Diese können zum Beispiel Weichmacher, wie Triphenylphosphat, oder Verlaufmittel, wie Siliconöle, sein.The layer contains substances which are added to the coating solution as conventional additives, which may be up to 5% by weight in the photoconductive layer. They improve the surface structure and the flexibility of the layer. These can be, for example, plasticizers, such as triphenyl phosphate, or leveling agents, such as silicone oils.

Die Erfindung wird anhand der folgenden Beispiele und Vergleichsbeispiele näher erläutert, ohne sie hierauf zu beschränken.The invention is explained in more detail with reference to the following examples and comparative examples, without restricting it thereto.

Beispiel 1example 1

Auf ein elektrochemisch vorbehandeltes und anodisiertes Aluminiumband, wie es als Träger für eine Offset-Druckplatte verwendet wird, wurde die folgende Dispersion so aufgetragen, daß sich ein Trockenschichtgewicht von 6 g/m2 ergab : 15,0 g N,N'-Dimethylperylen-3,4,9,10-tetracarbonsäurediimid (C. I. 71 130, Formel II) wurden in eine Lösung von 10,0 g eines Copolymerisates aus Vinylacetat und Crotonsäure (RMowilith Ct 5, Hoechst AG) in 200 g Tetrahydrofuran eingetragen und durch Mahlen in einer Kugelmühle während 2 Stunden dispergiert und anschließend 10 g 2,5-Bis-(4-diethylaminophenyl)-oxdiazol-1,3,4, 0,1 g eines Silikonöls der Viskosität 5 bis 20 mPa - s, sowie 65,0 g des obengenannten Copolymerisates in 700 g Tetrahydrofuran zugesetzt.The following dispersion was applied to an electrochemically pretreated and anodized aluminum tape, as used as a support for an offset printing plate, so that a dry layer weight of 6 g / m 2 resulted: 15.0 g of N, N'-dimethylperylene 3,4,9,10-tetracarboxylic acid diimide (CI 71 130, formula II) were introduced into a solution of 10.0 g of a copolymer of vinyl acetate and crotonic acid ( R Mowilith Ct 5, Hoechst AG) in 200 g of tetrahydrofuran and by grinding in dispersed in a ball mill for 2 hours and then 10 g of 2,5-bis (4-diethylaminophenyl) oxdiazole-1,3,4, 0.1 g of a silicone oil with a viscosity of 5 to 20 mPa.s, and 65.0 g of the above-mentioned copolymer in 700 g of tetrahydrofuran.

Die nach dem Trocknen erhaltene Schicht ist dunkelrot und matt.The layer obtained after drying is dark red and matt.

Die erhaltenen Daten sind in der angefügten Tabelle aufgeführt.The data obtained are shown in the attached table.

Beispiel 2Example 2

15,0 g Hostapermorange GR (Pigment Orange 43, C.I. 71 105, Formel 1) wurden in einer Lösung von 10 g Polybutylmethacrylat (RPlexigum P 676, Röhm GmbH) in 200 g Tetrahydrofuran eingetragen und durch Mahlen in einer Kugelmühle während 2 stunden dispergiert. Nach Zusatz von 3 g 2,5-Bis-(4-diethylaminophenyl)-oxdiazol-1,3,4 und 32 g Polymethylmethacrylat (RPlexigum M 345) in 340 g Tetrahydrofuran wurde die Schicht mit einem Schichtgewicht von 6 g/m2 auf aluminiumbedampfte Polyethylenterephthalatfolie aufgetragen und getrocknet.15.0 g of Hostapermorange GR (Pigment Orange 43, CI 71 105, Formula 1) were introduced into a solution of 10 g of polybutyl methacrylate ( R Plexigum P 676, Röhm GmbH) in 200 g of tetrahydrofuran and dispersed by grinding in a ball mill for 2 hours . After adding 3 g of 2,5-bis- (4-diethylaminophenyl) -oxdiazole-1,3,4 and 32 g of polymethyl methacrylate ( R Plexigum M 345) in 340 g of tetrahydrofuran, the layer with a layer weight of 6 g / m 2 applied to aluminum-coated polyethylene terephthalate film and dried.

Beispiel 3Example 3

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß anstelle des genannten Oxdiazols 1,5-Di-phenyl-3-p-methoxyphenyl-pyrazolin nach DE-AS 10 60 714, entsprechend US-PS 3, 180, 729, und anstelle des Polybutylmethacrylates und des Polymethylmethacrylates ein Terpolymerisat aus Styrol, Hexylmethacrylat und Methacrylsäure im Molverhältnis 10 : 60 : 30 verwendet wurde. Die Beschichtung erfolgte auf aufgerauhtes und anodisiertes Aluminiumträgermaterial in einer Schichtdicke von etwa 6 g/m2.The procedure was as in Example 2, with the difference that, instead of the oxdiazole mentioned, 1,5-diphenyl-3-p-methoxyphenylpyrazoline according to DE-AS 10 60 714, corresponding to US Pat. No. 3, 180, 729, and instead of the polybutyl methacrylate and the polymethyl methacrylate, a terpolymer of styrene, hexyl methacrylate and methacrylic acid in a molar ratio of 10:60:30 was used. The coating was carried out on roughened and anodized aluminum support material in a layer thickness of about 6 g / m 2 .

Die Schicht wurde nach Aufladen und Bildmäßigem Belichten mit einem Trockenentwickler behandelt. Sie ließ sich nach dem Fixieren mit einer handelsüblichen Entschichterlösung gruhdfrei entschichten. Die erhaltene Offset-Druckplatte zeigte eine hohe Auflösung und ergab in einem Druckversuch gute Druckqualitäten bis zu einer Auflage von weit über 100 000.The layer was treated with a dry developer after charging and imagewise exposure. After fixing it, it was possible to decoat with a commercially available decoater solution. The resulting offset printing plate showed a high resolution and, in a printing test, gave good printing qualities up to a print run of well over 100,000.

Beispiel 4Example 4

Es wurde verfahren wie in Beispiel 3, mit dem Unterschied, daß anstelle des Pyrazolins 4-Methoxybenzaldehyd-diphenylhydrazon (DE-OS 32 46 036) und anstelle von Hostapermorange GR als Farbstoff N,N'-(3-methoxypropyl)perylen-tetracarbonsäure-3,4,9,10-diimid (RPaliogen-schwarz, BASF AG) verwendet wurde.The procedure was as in Example 3, with the difference that instead of pyrazoline, 4-methoxybenzaldehyde diphenylhydrazone (DE-OS 32 46 036) and instead of Hostapermorange GR as dye N, N '- (3-methoxypropyl) perylene-tetracarboxylic acid- 3,4,9,10-diimide ( R Paliogen-black, BASF AG) was used.

Beispiel 5Example 5

20,0 g N,N'-Dimethylperylen-3,4,9,10-tetracarbonsäurediimid (C. I. 71 130, Formel 11), wie in Beispiel 1, wurden in eine Lösung von 20 g eines Polycarbonates (RMakrolon 2405, Bayer AG) in 200 g Tetrahydrofuran eingetragen und während 2 Stunden in einer Kugelmühle dispergiert und anschließend auf aluminiumbedampfte Polyethylenterephthalatfolie mit einem Trockenschichtgewicht von 6 g/m2 aufgetragen.20.0 g of N, N'-dimethylperylene-3,4,9,10-tetracarboxylic acid diimide (CI 71 130, formula 11), as in Example 1, were dissolved in a solution of 20 g of a polycarbonate ( R Makrolon 2405, Bayer AG ) entered in 200 g of tetrahydrofuran and dispersed for 2 hours in a ball mill and then applied to aluminum-coated polyethylene terephthalate film with a dry layer weight of 6 g / m 2 .

Beispiel 6Example 6

Es wurde verfahren wie in Beispiel 1, mit dem Unterschied daß die Schicht mit einer Schichtdicke von 20 g/m2 auf den Schichtträger aufgetragen wurde.The procedure was as in Example 1, with the difference that the layer was applied to the layer support with a layer thickness of 20 g / m 2 .

Trotz des um einen Faktor 3,3 erhöhten Schichtgewichtes wird kein erhöhtes Restpotential nach Belichtung mit Weißlicht der Energie 30 JMl/cm2 beobachtet.Despite the layer weight being increased by a factor of 3.3, no increased residual potential is observed after exposure to white light of the energy 30 J ml / cm 2 .

Beispiel 7Example 7

Es wurde verfahren wie in Beispiel 3, mit dem Unterschied, daß anstelle des anodisierten Aluminiumträgers Kupferkaschierte Polyimidfolie verwendet wurde. Die bei Photoleitermonoschichten mit höheren Anteilen an Photoleiter beobachteten Vergiftungseffekte, zum Beispiel bekannt aus deutscher Patentanmeldung, Aktenzeichen P 33 29 442, die zu einer starken Reduzierung der Ladungsannahme führen, wurden bei den in diesem Beispiel angewandten niedrigen Konzentrationen des gelösten Photoleiters nicht beobachtet. Die so erhaltene, beschichtete Folie ließ sich nach dem Bebildern und Fixieren des Tonerbilds an den nicht von Toner bedeckten Stellen einwandfrei entschichten. Durch Wegätzen der darunter befindlichen Metallbereiche wurden hochwertige, flexible Leiterplatten erhalten.The procedure was as in Example 3, with the difference that copper-clad polyimide film was used instead of the anodized aluminum support. The poisoning effects observed in photoconductor monolayers with higher proportions of photoconductor, for example known from German patent application, file number P 33 29 442, which lead to a strong reduction in the charge acceptance, were not observed at the low concentrations of the dissolved photoconductor used in this example. The coated film obtained in this way could be stripped perfectly after the imaging and fixing of the toner image at the areas not covered by toner. High-quality, flexible printed circuit boards were obtained by etching away the metal areas underneath.

Beispiel 8Example 8

Es wurde, wie in den vorherigen Beispielen beschrieben, zunächst eine Schicht aus 25 Gew.% Hostapermorange GR und 75 Gew.% des Terpolymerisates aus Beispiel 3 mit einem Schichtgewicht von 3 g/m2 auf anodisierten Aluminiumträger aufgetragen. Auf dieser Unterschicht wurde ein Deckstrich aus 25 Gew.% Hostapermorange GR, 20 Gew.% 2,5-Bis-(4-diethylaminophenyl)-oxdiazol-1,3,4 und 55 Gew.% des Terpolymerisates mit einem Schichtgewicht von 3 g/m2 aufgebracht.As described in the previous examples, a layer of 25% by weight of Hostapermorange GR and 75% by weight of the terpolymer from Example 3 with a layer weight of 3 g / m 2 was first applied to anodized aluminum supports. A top coat of 25% by weight of Hostapermorange GR, 20% by weight of 2,5-bis- (4-diethylaminophenyl) -oxdiazole-1,3,4 and 55% by weight of the terpolymer was coated on this underlayer with a layer weight of 3 g / m 2 applied.

Beispiel 9Example 9

Analog Beispiel 8 wurde ein Vorstrich (Unterschicht) von 6 g/m2 auf einen anodisierten Aluminiumträger aufgebracht. Die getrocknete Schicht wurde dann mit einer Lösung aus 5 Gew.% 2,5-Bis-(4-diethylaminophenyl)-oxdiazol-1,3,4 in Tetrahydrofuran behandelt und erneut getrocknet. Analoge Ergebnisse lassen sich durch Behandlung des noch feuchten Vorstriches mit einer Oxdiazol-Lösung erzielen (Naß-in-Naß-Beschichtung).Analogously to Example 8, a primer (undercoat) of 6 g / m 2 was applied to an anodized aluminum support. The dried layer was then treated with a solution of 5% by weight of 2,5-bis (4-diethylaminophenyl) oxdiazole-1,3,4 in tetrahydrofuran and dried again. Analogous results can be achieved by treating the still wet primer with an oxdiazole solution (wet-on-wet coating).

Beispiel 10Example 10

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß anstelle der Methacrylate ein Polyester (RDynapol L206, Dynamit Nobel AG) verwendet wurde. Das so erhaltene Material hatte eine hohe Flexibilität bei guter Haftung der Schicht auf dem Schichtträger. Es zeigte auch bei Einsatz in cyclisch arbeitenden Kopiergeräten keine Veränderung der elektrophotographischen Eigenschaften mit der Anzahl der Aufladungs- und Belichtungscyclen.The procedure was as in Example 2, with the difference that a polyester ( R Dynapol L206, Dynamit Nobel AG) was used instead of the methacrylates. The material thus obtained had a high degree of flexibility with good adhesion of the layer to the support. Even when used in cyclic copiers, it showed no change in the electrophotographic properties with the number of charging and exposure cycles.

Beispiel 11Example 11

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß anstelle des Terpolymerisates ein Polyurethan (RDesmolac 2100, Bayer AG) verwendet wurde.The procedure was as in Example 2, with the difference that a polyurethane ( R Desmolac 2100, Bayer AG) was used instead of the terpolymer.

Beispiel 12Example 12

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß als Photoleiter Polyvinylcarbazol (RLuvikan, BASF AG) und als Pigment N,N'-Dimethylperylen-3,4,9,10-tetracarbonsäurediimid verwendet wurden.The procedure was as in Example 2, with the difference that polyvinylcarbazole ( R Luvikan, BASF AG) was used as the photoconductor and N, N'-dimethylperylene-3,4,9,10-tetracarboxylic acid diimide was used as the pigment.

Beispiel 13Example 13

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß als Pigment Hostapermscharlach GO (Formel IV, C. I. 59300) eingesetzt wurde.The procedure was as in Example 2, with the difference that Hostapermscharlach GO (Formula IV, C.I. 59300) was used as pigment.

Beispiel 14Example 14

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß als Pigment Indanthrengoldgelb RK (Formel 111, R = Br) eingesetzt wurde, der Photoleiteranteil betrug 20 Gew.%.The procedure was as in Example 2, with the difference that the pigment used was indanthrene gold yellow RK (formula 111, R = Br), the proportion of photoconductor was 20% by weight.

Beispiel 15Example 15

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß als Pigment eine Verbindung der Formel 1, R = N02, eingesetzt wurde, der Photoleiteranteil betrug 20 Gew.%.The procedure was as in Example 2, with the difference that a compound of the formula 1, R = NO 2 , was used as pigment, the proportion of photoconductor was 20% by weight.

Vergleichsbeispiel 1Comparative Example 1

Auf einen aufgerauhten und anodisierten Aluminiumdruckplattenträger wurde eine Lösung aus 50 g eines Copolymerisates aus Styrol und Maleinsäureanhydrid, Zersetzungspunkt 200 bis 240°C, 50 g 2,5-Bis-(4-diethyl-aminophenyl)-oxdiazol-1,3,4, gelöst in 900 g Tetrahydrofuran, unter Zusatz von 0,1 g Silikonöl und 0,5 g Rhodamin B (C. I. 45170), gelöst in 5 g Methanol, aufgebracht und getrocknet.A solution of 50 g of a copolymer of styrene and maleic anhydride, decomposition point 200 to 240 ° C., 50 g of 2,5-bis- (4-diethyl-aminophenyl) -oxdiazole-1,3,4, was placed on a roughened and anodized aluminum printing plate support. dissolved in 900 g tetrahydrofuran, with the addition of 0.1 g silicone oil and 0.5 g rhodamine B (CI 45170), dissolved in 5 g methanol, applied and dried.

Vergleichsbeispiel 2Comparative Example 2

Auf einen aufgerauhten und anodisierten Aluminiumdruckplattenträger wurde die folgende Dispersion so aufgetragen, daß sich ein Trockenschichtgewicht von 3 g/m2 ergab : 50 g eines Copolymerisates aus Styrol und Maleinsäureanhydrid wurden in 950 g Tetrahydrofuran unter Zusatz von 0,1 g Siliconöl gelöst. In der Lösung wurden 2 g N,N'-Dimethylperylen-3,4,9.10-tetracarbonsäurediimid (C. I. 71130) durch Mahlen in einer Kugelmühle innerhalb von 2 Stunden dispergiert. Nach dem Trocknen wurde auf diese Ladungsträger erzeugende Schicht eine Ladungstransportschicht aus folgender Lösung aufgebracht, Trockenschichtgewicht ebenfalls 3 g/m2: 50 g eines Copolymerisates aus Styrol und Maleinsäureanhydrid und 50 g 2,5-Bis-(4-diethylamino-phenyl)-oxdiazol-1,3,4 wurden in 700 g Tetrahydrofuran und 250 g Butylacetat unter Zusatz von 0,1 g Siliconöl gelöst.The following dispersion was applied to a roughened and anodized aluminum printing plate support in such a way that a dry layer weight of 3 g / m 2 resulted: 50 g of a copolymer of styrene and maleic anhydride were dissolved in 950 g of tetrahydrofuran with the addition of 0.1 g of silicone oil. 2 g of N, N'-dimethylperylene-3,4,9,10-tetracarboxylic acid diimide (CI 71130) were dispersed in the solution by grinding in a ball mill within 2 hours. After drying, a charge transport layer from the following solution was applied to this charge carrier-generating layer, dry layer weight likewise 3 g / m 2 : 50 g of a copolymer of styrene and maleic anhydride and 50 g of 2,5-bis (4-diethylamino-phenyl) oxdiazole -1.3.4 were dissolved in 700 g of tetrahydrofuran and 250 g of butyl acetate with the addition of 0.1 g of silicone oil.

Vergleichsbeispiel 3Comparative Example 3

Auf einen aufgerauhten und anodisierten Aluminiumdruckplattenträger wurde eine Monoschicht des Schichtgewichtes 6 g/m2 aus folgender Dispersion aufgetragen : 6,25 g Hostapermorange GR und 4,2 g des Terpolymerisates aus Beispiel 3 wurden in 50 g Tetrahydrofuran durch 2-stündiges Mahlen in einer Kugelmühle dispergiert bzw. gelöst und dann zu einer Lösung aus 50 g 2,5-Bis-(4-diethylaminophenyl)-oxdiazol-1,3,4, 40 g des Terpolymerisates aus Beispiel 3 und 0,1 g Siliconöl in 850 g Tetrahydrofuran gegeben. Dieses Beispiel entspricht einer empfindlichen Monoschichtformulierung, die in US-PS 3,879,200 beschireben ist.A monolayer with a layer weight of 6 g / m 2 from the following dispersion was applied to a roughened and anodized aluminum printing plate support: 6.25 g of Hostapermorange GR and 4.2 g of the terpolymer from Example 3 were in 50 g of tetrahydrofuran by milling in a ball mill for 2 hours dispersed or dissolved and then added to a solution of 50 g of 2,5-bis (4-diethylaminophenyl) -oxdiazole-1,3,4, 40 g of the terpolymer from Example 3 and 0.1 g of silicone oil in 850 g of tetrahydrofuran . This example corresponds to a sensitive monolayer formulation described in U.S. Patent 3,879,200.

Vergleichsbeispiel 4Comparative Example 4

Es wurde verfahren wie in Beispiel 3, mit dem Unterschied, daß anstelle des Methacrylat-Terpolymerisates ein ebenfalls wäßrig-alkalisch entschichtbares Sulfonylurethan (hergestellt nach DE-OS 32 10 577, Beispiel 1) verwendet wurde.The procedure was as in Example 3, with the difference that instead of the methacrylate terpolymer, a likewise aqueous-alkaline decoatable sulfonyl urethane (prepared according to DE-OS 32 10 577, Example 1) was used.

Vergleichsbeispiel 5Comparative Example 5

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß anstelle der Methacrylate Cellulosenitrat mit einem Nitrierungsgrad von 12,2% eingesetzt wurde.The procedure was as in Example 2, with the difference that cellulose nitrate with a degree of nitration of 12.2% was used instead of the methacrylates.

Vergleichsbeispiel 6Comparative Example 6

Es wurde verfahren wie in Beispiel 2, mit dem Unterschied, daß anstelle der Methacrylate Polystyrol eingesetzt wurde.The procedure was as in Example 2, with the difference that polystyrene was used instead of the methacrylates.

Vergleichsbeispiel 7Comparative Example 7

Es wurde verfahren wie in Beispiel 3, mit dem Unterschied, daß anstelle des trans-Perinons Hostapermorange GR die analoge cis-Verbindung Permanent-rot TG01 der Hoechst AG (C. I. 71110) verwendet wurde.The procedure was as in Example 3, with the difference that instead of the trans-Perinon Hostapermorange GR, the analog cis compound Permanent red TG01 from Hoechst AG (C.I. 71110) was used.

Die Resultate der elektrophotographischen Untersuchungen der gemäß den Beispielen hergestellten Schichten sind in der folgenden Tabelle zusammengefaßt. Dabei bedeuten E½, E¼, und E⅛ die Belichtungsenergien, die bei einer Lichtintensität von 3/µW/cm2 aufgebracht werden müssen, um eine Entladung von -400 V auf -200 V, -100 V bzw. -50 V zu erreichen.

Figure imgb0005
The results of the electrophotographic examinations of the layers produced according to the examples are summarized in the following table. E½, E¼, and E⅛ mean the exposure energies that have to be applied at a light intensity of 3 / µW / cm 2 in order to achieve a discharge from -400 V to -200 V, -100 V and -50 V, respectively.
Figure imgb0005

Claims (13)

1. Electrophotographic recording material comprising an electrically conductive support, optionally an insulating barrier layer, and a photoconductive layer, whereby the photoconductive layer comprises at least one organic, n-type conducting pigment, at least one electronically inert, carbonyl-group containing binder and a photoconductor, characterizied in that the organic, n-type conducting pigment, which represents a compound from the class of trans-perinones, of perylene-tetracarboxylic acid diimides, or of condensed quinones, is present in the photoconductive layer in a concentration between 10 and 50 percent by weight, relative to the layer weight, and in that the photoconductor, which is an organic, p-type conducting photoconductor, is present in the photoconductive layer in a concentration of zero to 20 percent by weight, relative to the layer weight.
2. A recording material as claimed in claim 1, wherein the organic, n-type conducting pigment is present in a concentration between 15 and 30 percent by weight and the organic, p-type conducting photoconductor is present in a concentration from 2 to 8 percent by weight, relative to the layer weight.
3. A recording material as claimed in claim 1 or 2, wherein the organic, n-type conducting pigment comprises Hostaperm Orange GR (C. I. 71105).
4. A recording material as claimed in claim 1 or 2, wherein the organic, n-type conducting pigment comprises N,N'-dimethylperylene-3,4,9,10-tetracarboxylic acid diimide (C. I. 71130).
5. A recording material as claimed in claim 1 or 2, wherein the organic, n-type conducting pigment comprises N,N°-bis-(methoxypropyl)-perylene-3,4,9,10-tetracarboxytic acid diimide.
6. A recording material as claimed in claim 1 or claim 2, wherein the electronically inert, carbonyl-group containing binder is soluble or dispersible in an aqueous alkaline solution.
7. A recording material as claimed in claim 6, wherein the electronically inert, carbonyl-group containing binder comprises a copolymer of methacrylic acid esters, methacrylic acid, optionally with additional monomers, such as acrylic acid and styrene.
8. A recording material as claimed in claim 7, wherein the electronically inert, carbonyl-group containing binder has a glass transition temperature above 40 °C.
9. A recording material as claimed in claim 1, wherein the electrically conductive support comprises aluminium.
10. A recording material as claimed in claim 1, wherein the electrically conductive layer support is comprised of copper or has a copper surface.
11. A recording material as claimed in claim 1, wherein the photoconductive layer has been transferred from an intermediate support to the electrically conductive layer support, by lamination under the action of heat and pressure.
12. A recording material as claimed in claim 1, wherein the photoconductive layer is formed of a bottom layer comprising an organic; n-type conducting pigment and an electronically inert binder and a covering layer comprising an organic, n-type conducting pigment, an electronically inert binder, and an organic, p-type conducting photoconductor.
13. A recording material as claimed in claim 12, wherein the bottom layer and the covering layer are present in a ratio of layer weights ranging between 10 : 1 and 1 : 10.
EP85105785A 1984-05-15 1985-05-10 Electrophotographic recording material Expired - Lifetime EP0161648B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85105785T ATE29603T1 (en) 1984-05-15 1985-05-10 ELECTROPHOTOGRAPHIC RECORDING MATERIAL.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19843417951 DE3417951A1 (en) 1984-05-15 1984-05-15 ELECTROPHOTOGRAPHIC RECORDING MATERIAL
DE3417951 1984-05-15

Publications (3)

Publication Number Publication Date
EP0161648A1 EP0161648A1 (en) 1985-11-21
EP0161648B1 true EP0161648B1 (en) 1987-09-09
EP0161648B2 EP0161648B2 (en) 1993-11-03

Family

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Family Applications (1)

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EP85105785A Expired - Lifetime EP0161648B2 (en) 1984-05-15 1985-05-10 Electrophotographic recording material

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US (1) US4668600A (en)
EP (1) EP0161648B2 (en)
JP (1) JPS60254142A (en)
AT (1) ATE29603T1 (en)
AU (1) AU574626B2 (en)
BR (1) BR8502270A (en)
CA (1) CA1259517A (en)
DE (2) DE3417951A1 (en)
ES (1) ES8607576A1 (en)
FI (1) FI851884L (en)
ZA (1) ZA853586B (en)

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Also Published As

Publication number Publication date
ES543034A0 (en) 1986-06-01
FI851884L (en) 1985-11-16
ES8607576A1 (en) 1986-06-01
US4668600A (en) 1987-05-26
AU4251385A (en) 1985-11-21
JPS60254142A (en) 1985-12-14
ATE29603T1 (en) 1987-09-15
DE3560608D1 (en) 1987-10-15
DE3417951A1 (en) 1985-11-21
ZA853586B (en) 1985-12-24
FI851884A0 (en) 1985-05-13
CA1259517A (en) 1989-09-19
EP0161648A1 (en) 1985-11-21
AU574626B2 (en) 1988-07-07
BR8502270A (en) 1986-01-14
EP0161648B2 (en) 1993-11-03

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